1. Field of the Invention
This invention relates to buried electrically conductive layers of metal in semiconductor devices and a method of forming the same.
2. Background of the Invention
Deep buried electrically conductive layers of metal are required in some electrical devices, particularly in some integrated circuits to serve as an electrical contact to semiconductor regions remotely located from exposed major surfaces. Heretofore, one practice of forming such a buried electrical layer is to form the region by diffusion in a body of semiconductor material. A layer of semiconductor material of suitable type conductivity is grown on the body and the diffused region to obtain the buried layer. Circuitry is then formed in the body and the newly grown material and the buried region employed for electrical contacting as required.
However, the prior art practices involve practices which inherently introduce contaminents which degrade the physical properties of the buried layer and the material of the body. In particular, contaminents are introduced by undesirable impurities in the material employed for diffusion and for growing semiconductor materials.
An object of this invention is to provide a new and improved buried electrically conductive metal layer in a body of semiconductor material which overcomes deficiencies of the prior art.
Another object of this invention is to provide a new and improved method for providing a buried electrically conductive metal layer in a body of semiconductor material.
Other objects of this invention will, in part, be obvious and will, in part, appear hereinafter.